注意

CREATE TABLE borrowed_book (
loaner_name CHAR(100) PRIMARY KEY,
date_borrowed DATE NOT NULL DEFAULT CURRENT DATE,
date_returned DATE,
book CHAR(20)
FOREIGN KEY book REFERENCES library_books (isbn),
);
--This statement creates a table for a library database to hold information on borrowed books.
--The default value for date_borrowed indicates that the book is borrowed on the day the entry is made.
--The date_returned column is NULL until the book is returned.

以下示例说明如何使用 C 样式注释：

CREATE TABLE borrowed_book (
loaner_name CHAR(100) PRIMARY KEY,
date_borrowed DATE NOT NULL DEFAULT CURRENT DATE,
date_returned DATE,
book CHAR(20)
FOREIGN KEY book REFERENCES library_books (isbn),
);
/* This statement creates a table for a library database to hold information on borrowed books.
The default value for date_borrowed indicates that the book is borrowed on the day the entry is made.
The date_returned column is NULL until the book is returned. */